We like to think of babies as being totally blank slates, open to all experiences and loving everyone and everything equally. Well, that's sort of true, but it turns out their brains can actually begin to tell the difference between races much earlier than you might think. A new study found that by the time they're nine months old, babies' brains become much better at recognizing faces and emotions of people who are in the racial groups with which they interact the most. Of course, that's typically their own race, and so it begins, a lifetime of subconsciously seeing the world as an us versus them kind of place.

Psychology researcher Lisa Scott and her colleagues at the University of Massachusetts Amherst studied 48 Caucasian babies who'd had little or no exposure to black people in their short lives. Each baby was given two tasks. The first gauged their ability to differentiate between two people from their own race and two people from another race that they weren't familiar with. The second task involved viewing "emotion faces," like happy and sad, that either did or didn't match a corresponding emotion sound like laughing or crying. While the babies did this, their brain activity was monitored.

What they found is that five-month-olds were able to tell faces of any race apart equally. But nine-month-olds had grown better at being able to tell the difference between two faces that were the same race as they were. As for gauging people's "emotion faces," the five-month-olds processed the information for all races in one place in their brain, but by the time they were nine months, the brain operated differently when analyzing faces of the baby's race versus other races. What's more is that in the time between when they're five and nine-month-old, the babies' brain actually switched the processing of this information from one region to another.

This suggests that as they grows babies are working on their ability to perceive what's most important in their environment and then specialize in it. At that age, it's largely their family members that are important—what with the feeding, clothing, and protecting they do—and they obviously tend to be of the same race as the baby. This learning to differentiae between races is similar to what we know about how babies learn language. Very young babies don't know which sounds are important, so they treat them all in the same way. But as they learn the language that's being spoken with them, they develop the ability to tell sounds from their language and other languages apart. They also get much better at telling apart sounds in their own language than they are in languages with which they're unfamiliar.

So does this mean we're inherently terrible racists who prefer to only pay attention to our own kind? Not exactly. However, that racist phenomenon in adults where someone says, "All [insert racial group here] people look alike," probably does have real roots in this skill that we hone so early. (Still not excusable in grownups.) But really these findings don't have much to do with race as we come to understand it as adults. As Scott explains,

These results suggest that biases in face recognition and perception begin in preverbal infants, well before concepts about race are formed. It is important for us to understand the nature of these biases in order to reduce or eliminate them.

And, while further research would need to be done to bear this out, it seems highly likely that the more diverse an environment a baby is raised in, the less pronounced this effect would become. The baby would essentially be forced to be a generalist, rather than a specialist, when it came to the way people looked. That would probably leave their brain a lot more flexible later in life when it came to thinking about racial divisions put in place by society, and who they perceived as different or an "outsider."